Congo’s Tanganyika province has seen a sharp escalation of violence since late last year, with new armed groups forming and an increase in attacks and the use of firearms, said UNHCR spokesman Andrej Mahecic. “We are warning today that a humanitarian disaster of extraordinary proportions is about to hit the south-eastern part of the Democratic Republic of the Congo, as the province of Tanganyika plunges further into violence, triggering spiralling displacement and human rights abuses,” he said.

Clashes between militias representing the Luba, a Bantu ethnic group, and Twa pygmies, have already been going on for more than four years, driven by inequalities between Bantu villagers and the Twa, a hunting and gathering people historically excluded from access to land and basic services.

Mahecic said the intercommunal violence had led to atrocities and mass displacement, but there had also been fierce clashes between the Congolese armed forces and militia groups since the end of January.

UNHCR partner agencies had documented about 800 “protection incidents” including killings, abductions and rape, in the first two weeks of February. But much of the violence was going on in areas that were impossible for aid workers to reach.

The “lion’s share” of abuses concerned extortion and illegal taxation, mostly carried out by Congolese armed forces at road blocks.

Tanganyika province is three times the size of Switzerland with a population of about 3 million, of whom 630,000 have been displaced by the fighting, a number that has almost doubled in a year.

Meanwhile, in the Ituri province in the north of the country, at least 90,000 children have been forced to flee from their homes amid an escalation of violence that has seen more than 70 villages burned.

The United Nations Children’s Fund reports that clashes between ethnic groups have displaced an estimated 66,000 children internally and sent another 25,000 seeking refuge in neighbouring Uganda.

Violence between different ethnic groups over land and cattle disputes erupted in December in the Djugu region and has intensified during February. More than 76 gun-weapon killings have been recorded, mostly against women and children. At least three health centres and seven schools have been looted or burned, depriving children of healthcare and education.

The UN agency says that many of the internally displaced have settled in churches, schools and hospitals around Bunia, the capital of Ituri province. They are exposed to bad weather and have limited access to food and clean water, running a serious risk of contracting diarrhoea and cholera. Nearby the hospital in Bunia, UNICEF and its partners identified 70 unaccompanied children and 245 separated from their families with an urgent need of care.

The conflict is part of a worsening humanitarian crisis in Congo. Militia violence has risen since President Joseph Kabila’s refused to step down when his constitutional mandate expired in 2016.

Congo’s military has largely stamped out an insurrection that displaced 1.5 million people in central Congo in 2016-17 but militias are increasingly active along the eastern borders with Uganda, Rwanda and Burundi.